The embodiments described herein relate generally to power systems and, more particularly, to a sensor probe for use in a sensor assembly and methods of assembling the sensor probe.
At least some known power generation systems include at least one component that may become damaged or worn over time. For example, at least some known power generation systems include machines, such as turbines, that include components such as, bearings, gears, and/or rotor blades that wear over time. Continued operation with a worn component may cause additional damage to other components or may lead to a premature failure of the component or system.
To detect component damage within machines, the operation of at least some known machines is monitored with a monitoring system. At least some known monitoring systems use sensor assemblies that may include proximity sensors and/or sensor probes that use microwave emitters to measure a vibration and/or a relative position of a machine component. More specifically, within at least some known sensor probes, an emitter is used to generate at least one forward propagating electromagnetic field from at least one microwave signal. The machine component may be measured and/or monitored when the machine component interacts with the forward propagating electromagnetic field. More specifically, a loading is induced to the emitter by the interaction between the component and the forward propagating electromagnetic field. Within such systems, the sensor probe is coupled via a data conduit to a signal processing device that generates a proximity measurement based on the loading induced to the emitter.
While such sensor assemblies are generally able to provide fairly accurate proximity measurements, the conduit connecting various components of the sensor assembly may emit small amounts of electromagnetic radiation. For example, the emitter generates at least one backward propagating electromagnetic field. As such, electromagnetic radiation is emitted from the emitter, and thus, the sensor assembly emits electromagnetic radiation as a result of extraneous currents that are channeled through the assembly. When impedance levels vary between the emitter, the data conduit, and the signal processing device, at least one common mode current is generated and channeled between the components. Moreover, the variance in the impedance levels of the components results in an electromagnetic potential that is transmitted to the conduit causing the conduit to radiate electromagnetic waves. Emitting such electromagnetic radiation within the sensor assembly causes the energy within the sensor assembly to be substantially reduced which results in the signal strength generated by the emitter being reduced. The reduced signal strength adversely limits the accuracy of the sensor assembly.